I just bought a Meizu M6 Miniplayer, which is a chinese music/picture/video flash player.
Available in 2/4/8 GB flash, white and black, they are slightly wider and thicker than a nano, but the screen is more than double the size of a nano and has much better resolution.
They require no drivers, and show up as a hard drive on your computer when plugged in, for simple drag and drop music, pictures, and movies, which means no need for crappy itunes anymore.
These play MP3, MP2, WMA, OGG audio files, AVI movie files, and BMP, JPEG and animated GIF picture files
It also has a decent to good FM tuner as well, which the nano does not have.
The Meizu M6 comes standard with an easy to use voice recorder.
The battery life kills that of an ipod nano; the company quotes it at 36 hours of mp3 playback per charge.
They are also cheaper than the nano. The 2 and 4 gig models can be had from several online retailers for under 100 dollars, and the 8 gb model was purchased from ebay for 170 shipped by yours truly.
Anyway, read some reviews online for this if you are in the market, they are all stellar. Ipod killer has been thrown around loosely in the industry, but this one really does.